Refinement - the third R of the 3Rs framework - involves improving experimental procedures, housing, and care to minimize pain, suffering, and distress in laboratory animals, with substantial advances being made across all major species.
Laboratory animal refinement represents the highest-impact opportunity within the current research system for reducing the welfare cost of animal experimentation. Unlike replacement and reduction, which require changing what research is done, refinement improvements can be implemented immediately within existing research programs. Historically, inadequate pain management in post-surgical laboratory animals was widespread due to concerns that analgesics would alter experimental outcomes - refinement research has shown this concern is largely unfounded and that unmanaged pain itself introduces greater experimental variability. The culture of care in research institutions - the daily commitment to animal welfare by technicians, veterinarians, and researchers - is the foundation of effective refinement.